es too many open files error

[2014-08-20 11:39:04,567][WARN ][cluster.service          ] [cloud101415282_dp_nm_ss_nop_sogou-op_org] failed to reconnect to node [cloud101414842_dp_nm_ss_nop_sogou-op_org][Yev9IrB0SmeBrbNuVU4nhA][cloud101414842.dp.nm.ss.nop.sogou-op.org][inet[/10.141.48.42:9300]]{max_local_storage_nodes=1, master=false}
org.elasticsearch.transport.ConnectTransportException: [cloud101414842_dp_nm_ss_nop_sogou-op_org][inet[/10.141.48.42:9300]] General node connection failure
        at org.elasticsearch.transport.netty.NettyTransport.connectToNode(NettyTransport.java:668)
        at org.elasticsearch.transport.netty.NettyTransport.connectToNode(NettyTransport.java:615)
        at org.elasticsearch.transport.TransportService.connectToNode(TransportService.java:129)
        at org.elasticsearch.cluster.service.InternalClusterService$ReconnectToNodes.run(InternalClusterService.java:515)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:745)
Caused by: org.elasticsearch.common.netty.channel.ChannelException: Failed to open a socket.
        at org.elasticsearch.common.netty.channel.socket.nio.NioClientSocketChannel.newSocket(NioClientSocketChannel.java:43)
        at org.elasticsearch.common.netty.channel.socket.nio.NioClientSocketChannel.<init>(NioClientSocketChannel.java:82)
        at org.elasticsearch.common.netty.channel.socket.nio.NioClientSocketChannelFactory.newChannel(NioClientSocketChannelFactory.java:212)
        at org.elasticsearch.common.netty.channel.socket.nio.NioClientSocketChannelFactory.newChannel(NioClientSocketChannelFactory.java:82)
        at org.elasticsearch.common.netty.bootstrap.ClientBootstrap.connect(ClientBootstrap.java:212)
        at org.elasticsearch.common.netty.bootstrap.ClientBootstrap.connect(ClientBootstrap.java:182)
        at org.elasticsearch.transport.netty.NettyTransport.connectToChannels(NettyTransport.java:699)
        at org.elasticsearch.transport.netty.NettyTransport.connectToNode(NettyTransport.java:647)
        ... 6 more
Caused by: java.net.SocketException: Too many open files
        at sun.nio.ch.Net.socket0(Native Method)
        at sun.nio.ch.Net.socket(Net.java:423)
        at sun.nio.ch.Net.socket(Net.java:416)
        at sun.nio.ch.SocketChannelImpl.<init>(SocketChannelImpl.java:104)
        at sun.nio.ch.SelectorProviderImpl.openSocketChannel(SelectorProviderImpl.java:60)
        at java.nio.channels.SocketChannel.open(SocketChannel.java:142)
        at org.elasticsearch.common.netty.channel.socket.nio.NioClientSocketChannel.newSocket(NioClientSocketChannel.java:41)
        ... 13 more